The aim of this study was to prepare proposals to improve the production of standard ABO isohemagglutinin serum kits based on an assessment of the phenotypic, temporal, and gender characteristics of the prevalence of high-titer regular antibodies of the ABO system. Materials and methods. In 2021—2023, the Republican Blood Center of the Ministry of Health of the Republic of Tatarstan conducted a study of the titer of natural group antibodies in blood samples of all donors, except for group AB, in order to detect high (1:256 and higher) titers necessary for the production of standard ABO isohemagglutinin serum. A total of 38,795 donors were examined, high-titer regular antibodies of the ABO system were detected in 58 (15.0 ‰O). The phenotypic, temporal, and gender characteristics of the occurrence of high-titer regular antibodies of the ABO system were assessed. Results. The proportion of women among donors was 29.8%. Over the entire observation period, high-titer regular antibodies of the ABO system were found in women by 19.3 ‰O more often than in men (p<0.001). The frequency of occurrence of high-titer regular antibodies of the ABO system has no gender differences in the O and A phenotypes and is significantly higher in female donors of the B phenotype by 51.0 ‰O (p<0.001). Anti-B are less common than anti-A by 11.8 ‰O (p<0.03). Conclusion. The revealed increased frequency of anti-A in female donors of the Republic of Tatarstan allows us to recommend examining no more than 50% of female donors for high-titer regular antibodies and completely abandoning the search for these antibodies in men of group B. Based on the experience of 2021—2023 such a reduction would amount to 8662 out of 38795 studies or a reduction in material and labor costs by 22.3%.

ABO blood group system, donors, blood components, immunohematology, antibodies, immune antibodies.